In photography, controlling the light amount is accomplished using a variable opening (or aperture) by which light enters a camera and a shutter time. However, this requires a camera instrument with additional mechanical properties that allow a user to adjust the variable opening from a lens or another part of the camera. Aperture size affects to the depth-of-field (DOF). Small aperture settings (e.g., high f-number, such as f/22) may increase the sharpness of distant objects, or in other words increases DOF, which means more elements of a picture, from foreground to background, become sharply focused. It is well known that small apertures are also used for landscape photographs. A larger aperture may create a bokeh effect when a photograph is taken. This can create a distinct sense of depth to a photograph, drawing the viewer into the picture. When the camera is focused on a point in a scene using a larger aperture, parts of the scene that are not within the focus may look extremely blurry relative to the object in focus.
While mobile cameras, such as digital cameras and mobile phone cameras have become more popular, due to size and cost concerns, mobile cameras typically do not feature a variable aperture.